Statistically speaking, the series' prime matchup figured to come in Saturday afternoon's clash at Citi Field -- weather-permitting, of course.
The Cardinals are set to call on Lance Lynn (8-1, 2.54 ERA), while the Mets, if the weather is clear, will turn to R.A. Dickey (7-1, 3.06) to follow-up Santana's historic performance.
With rain in the forecast, however, Mets manager Terry Collins said he might call on Jeremy Hefner to fill in for the knuckleballer.
"We are going to watch the weather very closely for [Saturday] and see what it's going to be," Collins said. "If we're going to play in a downpour [Saturday], we have to decide whether or not that's the best conditions for R.A. to go out in."
If it is Dickey, he'll be coming off one of his best outings of the year on Tuesday, in which he struck out 10 batters over 7 1/3 shutout innings. That gem came on the heels of an 11-strikeout performance while allowing just one run over seven innings in his prior start.
With a victory in just his 12th start of the year on Saturday, the righty would match his win total from all of last season (32 starts). The scariest part for opponents might be the fact that the 37-year-old feels he is just finally starting to master the deceptive knuckleball.
As for Lynn, the 25-year-old righty has exceeded all expectations while filling in for injured ace Chris Carpenter. After entering Spring Training with his role undefined, Lynn now finds himself tied for the Major League lead with eight wins.
"He's done a great job and has continued to improve and make the adjustments that he needs to," Cardinals manager Mike Matheny said. "Lance has done a terrific job. He just wants to keep getting better. He has a lot of fight in him."
Cardinals: Matheny looks for positives amid struggles
Friday's series-opening loss marked the third straight for the Cardinals and extended the club's recent struggles. Since May 11, St. Louis has gone just 7-14 and watched its 3 1/2-game lead in the NL Central disappear, as the Cards fell into second place behind the Reds.
With 110 games left, Matheny is nowhere near ready to reach for the panic button. Instead, he's looking at the slide as a necessary part of the team's attempt to defend last year's title run.
"I believe that helps to develop the character," Matheny said. "That truly comes through later in the season. We're still in that phase of defining that. In my opinion, I don't think we've shown our best baseball yet.
"There were a lot of games that got by us that should have been ours. You've seen a lot of teams that are having good runs. We haven't had that good long run yet. I think times like we've just finished help define what's still ahead for us."
Mets: Rotation shuffle on the way
Collins will definitely be shaking up the Mets' rotation in the near future, so the only question now is when the changes will begin.
The expected rain could force Collins to start the mix-up as early as Saturday, with Hefner taking the hill instead of on his scheduled Monday start. If Hefner doesn't take the mound Saturday, that Monday start may never come, with both Miguel Batista and Chris Young nearing returns from the disabled list.
Collins said Young's rehab start at Triple-A Buffalo on Thursday, in which he tossed six scoreless innings, might have been his last before returning to the Mets. Batista, meanwhile, is eligible to return Monday.
The Mets and Cardinals have split each of the last two season series, winning three games apiece.
With Friday's loss, the Cardinals fell to 3-8 against the NL East this season. They have a 24-16 record against the rest of the NL.
Santana's no-hitter Friday night left the Padres as the lone franchise without a no-hitter.